The present invention provides a background music play device equipped in a mobile station and methods for playing the background music capable of playing the background music during voice communication between two mobile stations. A background music play device for a mobile station of the present invention includes storage means for storing digital music file; music file play means for playing the digital music file stored in the storage means; output means for outputting voice of caller and music played by the music file play means; input means for inputting voice of receiver; control means which control signal transmittance and receipt, encoding signals to be transmitted and decoding signals received, and outputting the music as a background music according to user's selection. Using the mobile station equipped with the background music play device, specific background music is preset relative to each phone number set in the mobile station such that the preset background music is automatically played when a communication channel is established with the mobile station having one of the preset phone numbers.

A Group Page process is implemented by which a variable audio source may be dynamically allocated circuit switch channels for broadcasting to a group of devices. The process is implemented via message exchanges between a Group Page Manager which accesses a data structure relating to the grouped devices, and a Paging Party Call Process associated with the party desirous of broadcasting an audio page.

A telecommunication and alarm system for connection to: a four-wire or two-wire telephone network, a two-terminal doorphone unit, and one or more alarm detectors connected in parallel COMPRISING a line and extension connection for communication with the "tip" and "ring" wires of the incoming telephone line and the service pair of wires enabling in-house plug-in installation of the inventive device; and an alternate extension connection for communication with the "tip" and "ring" pair of the telephone wires leading to the in-house single-line extension telephones; a plurality of connection modules each equipped with a slide entry plug and a slide entry jack, the plug end of which to be inserted within the telephone wall outlet, and the jack of which to receive the telephone cord of the extension telephone set; an input connection for unidirectional communication with a two-terminal doorphone unit, from any in-house extension telephone, and means to toggle the direction of speech upon pulsing one same digit on the extension telephone keypad; means for generating sequencing ring tones to the extension sets and for powering said extensions sets achieving complete intercommunication between said extension sets; means for detecting tone signals and hook status of the extensions telephones, for detecting ring tones and tone status signals from the external telephone line, and for generating automated tone dialing on the external telephone line; an input connection for one or various alarm detectors; an output connection for activating a tape cassette recorder upon off-hook status of any one extension set and for recording the audio signals of the telephone calls; an output connection for a doorstrike in order for the in-house user to open an entrance door or gate by hitting a key on the telephone set keypad after accessing the doorphone; computing means to support all hereby operating characteristics automatically and by response to user coded commands input from the extension sets while off-hook.

A facility is provided in wireless communications system which causes a base station to substitute predetermined signals for speech and/or noise signals that are received from a wireless station that has entered a muting request, in which the predetermined signals, may be, for example, silence.

The PBX system includes an analog to digital, and digital to analog, (A/D) conversion where the sample size and the sample rate are selectively adjustable. The A/D structure includes registers which hold values indicating the sample size and the sample rate for the conversion. When the A/D structure is configured, the A/D structure reads the values in the register and configures itself to the sample rate and sample size indicated by the registers. When the sample size and sample rate is to be changed, the values in the registers are changed and the A/D structure is reconfigured.